Recombinant Escherichia coli BL21 is used to produce human-like collagen. The key constituents of media are optimized using response surface methodology (RSM). Before thermal induction, the highest biomass production ...Recombinant Escherichia coli BL21 is used to produce human-like collagen. The key constituents of media are optimized using response surface methodology (RSM). Before thermal induction, the highest biomass production and the lowest production of some hazardous by-products, especially acetic acid, were obtained in the media containing 0.085 mol·L-1 glucose and 0.019 mol·L-1 nitrogen (carbon-nitrogen ratio, 4.47:1). After thermal induction, when the concentrations of glucose and nitrogen in the media were 0.065 mol·L-1 and 0.017 mol·L-1 , respectively (carbon-nitrogen ratio, 3.82:1), the productivity of human-like collagen per cell was the highest while that of acetic acid was the lowest. The extended analysis showed that the production of lactic acid and propionic acid increased while that of some intermediate acids of the tricarboxylic acid cycle decreased if the dose of glucose increased.展开更多
Recombinant E. coli BL 21 was cultivated in high cell density to produce human-like collagen. The effects of the feeding of nitrogen source, controlled by an auto on/off-feeding mode with two different cycles of 0.5mi...Recombinant E. coli BL 21 was cultivated in high cell density to produce human-like collagen. The effects of the feeding of nitrogen source, controlled by an auto on/off-feeding mode with two different cycles of 0.5min and 4min intervals, oxygen-enrichment methods and inducement strength on the cell yield and human-like collagen production were investigated. The studies showed that nitrogen source feeding in fast cycle could result in higher human-like collagen production than that in slow cycle; and the feedback regulation of glucose, increase of the pressure of fermentation bioreactor, and supply of oxygen-enriched air could all increase cell yield and human-like collagen production. The effects of inducement strength on protein expression were found important. When OD600 reached 90-100, the cultivation temperature was increased to 42℃ to begin induction for 2-3 h, and then shifted to 39℃ for 5-6h induction, the cell density and human-like collagen production could reach 96g·L-1 [DCW (dry cell mass)] and 19.8% (g·g-1 DCW) respectively.展开更多
In order to improve the production of human-like collagen III(HLC III)by fed-batch culture of recombinant Escherichia coli BL21,the Plackett-Burman and Box-Behnken design were applied to optimize the fermentation proc...In order to improve the production of human-like collagen III(HLC III)by fed-batch culture of recombinant Escherichia coli BL21,the Plackett-Burman and Box-Behnken design were applied to optimize the fermentation process parameters.Three variables(induction time,inoculum age and pH),which have significant effects on HLC III production,were selected from eight variables by Plackett-Burman design.With the regression coefficient analysis in the Box-Behnken design,a relationship between HLC III production and three significant factors was obtained,and the optimum levels of the three variables were as follows:induction time 3.2h,inoculum age 12.6 h and pH 6.7.The 3D response surface plots and 2D contour plots created by the Box-Behnken design showed that the interaction between induction time and pH and that between innoculum age and pH were significant.An average 9.68 g·L1HLC III production was attained in the validation experiment under optimized condition,which was 80%higher than the yield of 5.36 g·L1before optimization.展开更多
The kinetics of batch and fed-batch cultures of recombinant Escherichia coli producing human-like collagen was investigated. In the batch culture, a kinetic model of a simple growth-association system was concluded wi...The kinetics of batch and fed-batch cultures of recombinant Escherichia coli producing human-like collagen was investigated. In the batch culture, a kinetic model of a simple growth-association system was concluded without consideration of cell endogeneous metabolism. The cell lag time, the maximum specific growth rate and Yx/s were determined as 1.75h, 0.65h^-1 and 0.51g·g^-1, respectively. In the fed-batch culture, different specific growth rates were set at （0.15, 0.2, 0.25h^-1） by the method of pseudo-exponential feeding, and the expressions for the specific rate of substrate consumption, the growth kinetics and the product formation kinetics of each phase were obtained. The result shows that the concentrations of cell and product can reach 77.5g·L^-1 and 10.2g·L^-1 respectively. The modal predictions are in good agreement with the experimental data.展开更多
With the maturation of autonomous driving technology, the use of autonomous vehicles in a socially acceptable manner has become a growing demand of the public. Human-like autonomous driving is expected due to the impa...With the maturation of autonomous driving technology, the use of autonomous vehicles in a socially acceptable manner has become a growing demand of the public. Human-like autonomous driving is expected due to the impact of the differences between autonomous vehicles and human drivers on safety.Although human-like decision-making has become a research hotspot, a unified theory has not yet been formed, and there are significant differences in the implementation and performance of existing methods. This paper provides a comprehensive overview of human-like decision-making for autonomous vehicles. The following issues are discussed: 1) The intelligence level of most autonomous driving decision-making algorithms;2) The driving datasets and simulation platforms for testing and verifying human-like decision-making;3) The evaluation metrics of human-likeness;personalized driving;the application of decisionmaking in real traffic scenarios;and 4) The potential research direction of human-like driving. These research results are significant for creating interpretable human-like driving models and applying them in dynamic traffic scenarios. In the future, the combination of intuitive logical reasoning and hierarchical structure will be an important topic for further research. It is expected to meet the needs of human-like driving.展开更多
By intercepting the most effective fragment of human collagen’s gene,recombinant human-like collagen is produced by genetic engineering technology and biotechnology.The collagen has good biocompatibility and can prom...By intercepting the most effective fragment of human collagen’s gene,recombinant human-like collagen is produced by genetic engineering technology and biotechnology.The collagen has good biocompatibility and can promote cell formation.Recombinant human-like collagen has great potential application value in medical biological materials,cosmetics and foods.In recent years,many specialized enterprises which are engaged in human-like collagen raw materials production have emerged.In this paper,a brief summary of the current recombinant human-like collagen raw material’s production and its latest research and development have been made.展开更多
Rapid advancements in automated vehicles(AVs)technology have transformed the measurability,controllability and unpredictability of transportation systems.Evaluating driving risk and effectively managing driving behavi...Rapid advancements in automated vehicles(AVs)technology have transformed the measurability,controllability and unpredictability of transportation systems.Evaluating driving risk and effectively managing driving behaviours is critical.AVs should be enabled to identify,analyse,evaluate and devise effective countermeasures for driving risk by autonomously learning from human driving experiences.This learning will enhance the interactive decision-making capabilities and achieve driving behaviours that reflect human-like logic.The primary challenge lies in integrating human-like logic and driving risk constraints based on behavioural decision-making outcomes.This integration is crucial to align the AVs’cognitive levels-movement,comprehension,memory and inference-more closely with human driving necessities,habits and styles.Such alignment holds the potential to improve the prediction and planning of future actions and facilitate the development of motion planning schemes geared towards minimizing driving risk.We performed a comprehensive review of AVs’behavioural decision-making and intelligent motion-planning research from 2000 to 2023 from four key perspectives-driving risk,human-like logic,behavioural decision making and motion planning.Based on the Web of Science and China National Knowledge Internet database,the results of our review indicate that significant progress has been made in AV behavioural decision making and intelligent motion planning over time.When AVs and human-driven vehicles coexist,greater incorporation of human-like logic is required.Guided by these findings,we delineate future development directions and propose a research paradigm for human-like logic and a research framework for human-like logic-driven behavioural decision making and intelligent motion planning of AVs.展开更多
Humans excel at dexterous manipulation;however,achieving human-level dexterity remains a significant challenge for robots.Technological breakthroughs in the design of anthropomorphic robotic hands,as well as advanceme...Humans excel at dexterous manipulation;however,achieving human-level dexterity remains a significant challenge for robots.Technological breakthroughs in the design of anthropomorphic robotic hands,as well as advancements in visual and tactile perception,have demonstrated significant advantages in addressing this issue.However,coping with the inevitable uncertainty caused by unstructured and dynamic environments in human-like dexterous manipulation tasks,especially for anthropomorphic five-fingered hands,remains an open problem.In this paper,we present a focused review of human-like dexterous manipulation for anthropomorphic five-fingered hands.We begin by defining human-like dexterity and outlining the tasks associated with human-like robot dexterous manipulation.Subsequently,we delve into anthropomorphism and anthropomorphic five-fingered hands,covering definitions,robotic design,and evaluation criteria.Furthermore,we review the learning methods for achieving human-like dexterity in anthropomorphic five-fingered hands,including imitation learning,reinforcement learning and their integration.Finally,we discuss the existing challenges and propose future research directions.This review aims to stimulate interest in scientific research and future applications.展开更多
Although significant advances in the design of soft robotic hands have been made to mimic the structure of the human hands,there are great challenges to control them for coordinated and human-like postures.Based on th...Although significant advances in the design of soft robotic hands have been made to mimic the structure of the human hands,there are great challenges to control them for coordinated and human-like postures.Based on the principle of postural synergies in the human hand,we present a synergistic approach for coordinated control of a soft robotic hand to replicate the human-like grasp postures.To this end,we firstly develop a kinematic model to describe the control variables and the various postures of the soft robotic hand.Based on the postural synergies,we use the developed model and Principal Component Analysis(PCA)method to describe the various postures of the soft robotic hand in a low-dimensional space formed by the synergies of actuator motions.Therefore,the coordinates of these synergies can be used as low-dimensional control inputs for the soft robotic hand with a higher-dimensional postural space.Finally,we establish an experimental platform on a customized soft robotic hand with6 pneumatical actuators to verify the effectiveness of the development.Experimental results demonstrate that with only a 2-dimensional control input,the soft robotic hand can reliably replicate 30 grasp postures in the Feix taxonomy of the human hand.展开更多
Effects of temperature on self-interaction of human-like collagen （HLC） were investigated by hydrophobic in- teraction chromatography, calorimetric measurement, and sodium dodecyl sulphate-polyacrylamide gel electro...Effects of temperature on self-interaction of human-like collagen （HLC） were investigated by hydrophobic in- teraction chromatography, calorimetric measurement, and sodium dodecyl sulphate-polyacrylamide gel electropho- resis （SDS-PAGE） analysis. Results show that three types of interaction roles may exist between ttLC molecules at 3--50 ℃, which were divided into three narrower temperature ranges. In temperature range from 3--22 ℃, hy- drogen bonding plays a key role in the formation of a gelatinous aggregate. In the range of 22--38 ℃, hydrophobic bonds accompanied by hydrogen bonds are involved in the formation compact aggregates. When temperature is above 38 ℃ the hydrophobic effect formed in the HLC monomer results in the loss of its ability to self-interact.展开更多
The purpose of this paper is to alleviate the potential safety problems associated with the human driver and the automatic system competing for the right of way due to different objectives by mitigating the human-mach...The purpose of this paper is to alleviate the potential safety problems associated with the human driver and the automatic system competing for the right of way due to different objectives by mitigating the human-machine conflict phenomenon in human-machine shared driving(HMSD)technology from the automation system.Firstly,a basic lane-changing trajectory algorithm based on the quintic polynomial in the Frenet coordinate system is developed.Then,in order to make the planned trajectory close to human behavior,naturalistic driving data is collected,based on which some lane-changing performance features are selected and analyzed.There are three aspects have been taken into consideration for the human-like lane-changing trajectory:vehicle dynamic stability performance,driving cost optimization,and collision avoidance.Finally,the HMSD experiments are conducted with the driving simulator to test the potential of the human-like lane-changing trajectory planning algorithm.The results demonstrate that the lane-changing trajectory planning algorithm with the highest degree of personalization is highly consistent with human driver behavior and consequently would potentially mitigate the human-machine conflict with the HMSD application.Furthermore,it could be further employed as an empirical trajectory prediction result.The algorithm employs the distribution state of the historical trajectory for human-like processing,simplifying the operational process and ensuring the credibility,integrity,and interpretability of the results.Moreover,in terms of optimization processing,the form of optimization search followed by collision avoidance detection is adopted to in principle reduce the calculation difficulty.Additionally,a new convex polygon collision detection method,namely the vertex embedding method,is proposed for collision avoidance detection.展开更多
基金Supported by the National High Technology Research and Development Program of China （2006AA02Z246 2007AA03Z456） the National Natural Science Foundation of China （20776119 21076169）+4 种基金 Xi’an Research and Development Program（CX0735） the Scientific Research Program of Shaanxi Provincial Department of Education China （07JK417 07JC16 JG08181） the Natural Science Foundation of Shaanxi Province （2010JQ2012） the Specialized Research Fund for the Doctoral Program of Higher Education of China （20096101120023 20096101110014） Shaanxi Key Subject Program China
文摘Recombinant Escherichia coli BL21 is used to produce human-like collagen. The key constituents of media are optimized using response surface methodology (RSM). Before thermal induction, the highest biomass production and the lowest production of some hazardous by-products, especially acetic acid, were obtained in the media containing 0.085 mol·L-1 glucose and 0.019 mol·L-1 nitrogen (carbon-nitrogen ratio, 4.47:1). After thermal induction, when the concentrations of glucose and nitrogen in the media were 0.065 mol·L-1 and 0.017 mol·L-1 , respectively (carbon-nitrogen ratio, 3.82:1), the productivity of human-like collagen per cell was the highest while that of acetic acid was the lowest. The extended analysis showed that the production of lactic acid and propionic acid increased while that of some intermediate acids of the tricarboxylic acid cycle decreased if the dose of glucose increased.
基金Supported by the National Science and Technology Key Funds (2003DA901A32)the National Nature Science Foundation (No. 20476085).
文摘Recombinant E. coli BL 21 was cultivated in high cell density to produce human-like collagen. The effects of the feeding of nitrogen source, controlled by an auto on/off-feeding mode with two different cycles of 0.5min and 4min intervals, oxygen-enrichment methods and inducement strength on the cell yield and human-like collagen production were investigated. The studies showed that nitrogen source feeding in fast cycle could result in higher human-like collagen production than that in slow cycle; and the feedback regulation of glucose, increase of the pressure of fermentation bioreactor, and supply of oxygen-enriched air could all increase cell yield and human-like collagen production. The effects of inducement strength on protein expression were found important. When OD600 reached 90-100, the cultivation temperature was increased to 42℃ to begin induction for 2-3 h, and then shifted to 39℃ for 5-6h induction, the cell density and human-like collagen production could reach 96g·L-1 [DCW (dry cell mass)] and 19.8% (g·g-1 DCW) respectively.
基金Supported by the National Natural Science Foundation of China（20776119） the National High Technology Research and Development Program of China（2007AA03Z456A） the Special Research Program of the Education Department of Shaanxi Province（07JK417）
文摘In order to improve the production of human-like collagen III(HLC III)by fed-batch culture of recombinant Escherichia coli BL21,the Plackett-Burman and Box-Behnken design were applied to optimize the fermentation process parameters.Three variables(induction time,inoculum age and pH),which have significant effects on HLC III production,were selected from eight variables by Plackett-Burman design.With the regression coefficient analysis in the Box-Behnken design,a relationship between HLC III production and three significant factors was obtained,and the optimum levels of the three variables were as follows:induction time 3.2h,inoculum age 12.6 h and pH 6.7.The 3D response surface plots and 2D contour plots created by the Box-Behnken design showed that the interaction between induction time and pH and that between innoculum age and pH were significant.An average 9.68 g·L1HLC III production was attained in the validation experiment under optimized condition,which was 80%higher than the yield of 5.36 g·L1before optimization.
基金Supported by the National Science and Technology Key Funds (2003DA901A32) and the National Natural Science Foundationof China (No.20476085).
文摘The kinetics of batch and fed-batch cultures of recombinant Escherichia coli producing human-like collagen was investigated. In the batch culture, a kinetic model of a simple growth-association system was concluded without consideration of cell endogeneous metabolism. The cell lag time, the maximum specific growth rate and Yx/s were determined as 1.75h, 0.65h^-1 and 0.51g·g^-1, respectively. In the fed-batch culture, different specific growth rates were set at （0.15, 0.2, 0.25h^-1） by the method of pseudo-exponential feeding, and the expressions for the specific rate of substrate consumption, the growth kinetics and the product formation kinetics of each phase were obtained. The result shows that the concentrations of cell and product can reach 77.5g·L^-1 and 10.2g·L^-1 respectively. The modal predictions are in good agreement with the experimental data.
基金supported by the National Key R&D Program of China (2022YFB2502900)the National Natural Science Foundation of China (62088102, 61790563)。
文摘With the maturation of autonomous driving technology, the use of autonomous vehicles in a socially acceptable manner has become a growing demand of the public. Human-like autonomous driving is expected due to the impact of the differences between autonomous vehicles and human drivers on safety.Although human-like decision-making has become a research hotspot, a unified theory has not yet been formed, and there are significant differences in the implementation and performance of existing methods. This paper provides a comprehensive overview of human-like decision-making for autonomous vehicles. The following issues are discussed: 1) The intelligence level of most autonomous driving decision-making algorithms;2) The driving datasets and simulation platforms for testing and verifying human-like decision-making;3) The evaluation metrics of human-likeness;personalized driving;the application of decisionmaking in real traffic scenarios;and 4) The potential research direction of human-like driving. These research results are significant for creating interpretable human-like driving models and applying them in dynamic traffic scenarios. In the future, the combination of intuitive logical reasoning and hierarchical structure will be an important topic for further research. It is expected to meet the needs of human-like driving.
文摘By intercepting the most effective fragment of human collagen’s gene,recombinant human-like collagen is produced by genetic engineering technology and biotechnology.The collagen has good biocompatibility and can promote cell formation.Recombinant human-like collagen has great potential application value in medical biological materials,cosmetics and foods.In recent years,many specialized enterprises which are engaged in human-like collagen raw materials production have emerged.In this paper,a brief summary of the current recombinant human-like collagen raw material’s production and its latest research and development have been made.
基金support of the National Natural Science Foundation of China(Grant No.72261021)the Science and Technology R&D Project of Yunnan Communications Investment&Construction Group CO,LTD.(Grant No.YCIC-YF-2021-05)the Research Project on Key Technologies for Road Safety and Disaster Mitigation and Prevention,Department of Transport of Yunnan Province,China(Grant No.SZKM202231022).
文摘Rapid advancements in automated vehicles(AVs)technology have transformed the measurability,controllability and unpredictability of transportation systems.Evaluating driving risk and effectively managing driving behaviours is critical.AVs should be enabled to identify,analyse,evaluate and devise effective countermeasures for driving risk by autonomously learning from human driving experiences.This learning will enhance the interactive decision-making capabilities and achieve driving behaviours that reflect human-like logic.The primary challenge lies in integrating human-like logic and driving risk constraints based on behavioural decision-making outcomes.This integration is crucial to align the AVs’cognitive levels-movement,comprehension,memory and inference-more closely with human driving necessities,habits and styles.Such alignment holds the potential to improve the prediction and planning of future actions and facilitate the development of motion planning schemes geared towards minimizing driving risk.We performed a comprehensive review of AVs’behavioural decision-making and intelligent motion-planning research from 2000 to 2023 from four key perspectives-driving risk,human-like logic,behavioural decision making and motion planning.Based on the Web of Science and China National Knowledge Internet database,the results of our review indicate that significant progress has been made in AV behavioural decision making and intelligent motion planning over time.When AVs and human-driven vehicles coexist,greater incorporation of human-like logic is required.Guided by these findings,we delineate future development directions and propose a research paradigm for human-like logic and a research framework for human-like logic-driven behavioural decision making and intelligent motion planning of AVs.
基金supported in part by the National Natural Science Foundation of China(91748131,62006229,and 61771471)in part by Young Scientists Fund of the National Natural Science Foundation of China(62303454)+1 种基金in part by the Strategic Priority Research Program of Chinese Academy of Science(XDB32050106)in part by the InnoHK Project.
文摘Humans excel at dexterous manipulation;however,achieving human-level dexterity remains a significant challenge for robots.Technological breakthroughs in the design of anthropomorphic robotic hands,as well as advancements in visual and tactile perception,have demonstrated significant advantages in addressing this issue.However,coping with the inevitable uncertainty caused by unstructured and dynamic environments in human-like dexterous manipulation tasks,especially for anthropomorphic five-fingered hands,remains an open problem.In this paper,we present a focused review of human-like dexterous manipulation for anthropomorphic five-fingered hands.We begin by defining human-like dexterity and outlining the tasks associated with human-like robot dexterous manipulation.Subsequently,we delve into anthropomorphism and anthropomorphic five-fingered hands,covering definitions,robotic design,and evaluation criteria.Furthermore,we review the learning methods for achieving human-like dexterity in anthropomorphic five-fingered hands,including imitation learning,reinforcement learning and their integration.Finally,we discuss the existing challenges and propose future research directions.This review aims to stimulate interest in scientific research and future applications.
基金supported by the National Natural Science Foundation of China(Grant Nos.52025057,91948302)the Science and Technology Commission of Shanghai Municipality(Grant No.20550712100)。
文摘Although significant advances in the design of soft robotic hands have been made to mimic the structure of the human hands,there are great challenges to control them for coordinated and human-like postures.Based on the principle of postural synergies in the human hand,we present a synergistic approach for coordinated control of a soft robotic hand to replicate the human-like grasp postures.To this end,we firstly develop a kinematic model to describe the control variables and the various postures of the soft robotic hand.Based on the postural synergies,we use the developed model and Principal Component Analysis(PCA)method to describe the various postures of the soft robotic hand in a low-dimensional space formed by the synergies of actuator motions.Therefore,the coordinates of these synergies can be used as low-dimensional control inputs for the soft robotic hand with a higher-dimensional postural space.Finally,we establish an experimental platform on a customized soft robotic hand with6 pneumatical actuators to verify the effectiveness of the development.Experimental results demonstrate that with only a 2-dimensional control input,the soft robotic hand can reliably replicate 30 grasp postures in the Feix taxonomy of the human hand.
文摘Effects of temperature on self-interaction of human-like collagen （HLC） were investigated by hydrophobic in- teraction chromatography, calorimetric measurement, and sodium dodecyl sulphate-polyacrylamide gel electropho- resis （SDS-PAGE） analysis. Results show that three types of interaction roles may exist between ttLC molecules at 3--50 ℃, which were divided into three narrower temperature ranges. In temperature range from 3--22 ℃, hy- drogen bonding plays a key role in the formation of a gelatinous aggregate. In the range of 22--38 ℃, hydrophobic bonds accompanied by hydrogen bonds are involved in the formation compact aggregates. When temperature is above 38 ℃ the hydrophobic effect formed in the HLC monomer results in the loss of its ability to self-interact.
基金Open Fund of State Key Laboratory of Automobile Simulation and Control of Jilin University(20201111).
文摘The purpose of this paper is to alleviate the potential safety problems associated with the human driver and the automatic system competing for the right of way due to different objectives by mitigating the human-machine conflict phenomenon in human-machine shared driving(HMSD)technology from the automation system.Firstly,a basic lane-changing trajectory algorithm based on the quintic polynomial in the Frenet coordinate system is developed.Then,in order to make the planned trajectory close to human behavior,naturalistic driving data is collected,based on which some lane-changing performance features are selected and analyzed.There are three aspects have been taken into consideration for the human-like lane-changing trajectory:vehicle dynamic stability performance,driving cost optimization,and collision avoidance.Finally,the HMSD experiments are conducted with the driving simulator to test the potential of the human-like lane-changing trajectory planning algorithm.The results demonstrate that the lane-changing trajectory planning algorithm with the highest degree of personalization is highly consistent with human driver behavior and consequently would potentially mitigate the human-machine conflict with the HMSD application.Furthermore,it could be further employed as an empirical trajectory prediction result.The algorithm employs the distribution state of the historical trajectory for human-like processing,simplifying the operational process and ensuring the credibility,integrity,and interpretability of the results.Moreover,in terms of optimization processing,the form of optimization search followed by collision avoidance detection is adopted to in principle reduce the calculation difficulty.Additionally,a new convex polygon collision detection method,namely the vertex embedding method,is proposed for collision avoidance detection.
